change container of device_state_flags from system to system_ext

This commit changes the container of device_state_flags from system to
system_ext, since the flag is used in the library and binaries installed
in system_ext partition.

Bug: 328444881
Test: presubmit
Change-Id: I586cf7e238d362175f6b90f8809f56577d6b19bb
2 files changed